The Baltimore Police Department has engaged in years of racially discriminatory policing that targeted black residents, illegally detaining and searching people and using excessive force, the Justice Department concludes in a report released Tuesday.

In a scathing review that includes the historical backdrop of Baltimore’s racially divided past, civil rights investigators declare that a “legacy of zero tolerance enforcement” that started in 1999 and officially ended a decade ago “continues to drive” the policing strategy of the city.

The federal investigators found that officers are poorly trained and that the department has fostered a culture in which complaints against police are often ignored. Most of the unconstitutional stops occurred in predominantly poor black neighborhoods, the report says, and some people were stopped simply because police perceived them as disrespectful.

The Justice Department concluded that the police force’s “relationship with certain Baltimore communities is broken.”

Baltimore State's Attorney Marilyn Mosby, center, speaks during a news conference after her office dropped remaining charges against the three Baltimore police officers who were still awaiting trial in Freddie Gray’s death on July 27. (Steve Ruark/AP)

“Racially disparate impact is present at every stage of BPD’s enforcement actions, from the initial decision to stop individuals on Baltimore streets to searches, arrests, and uses of force. These racial disparities, along with evidence suggesting intentional discrimination, erode the community trust that is critical to effective policing,” the 163-page report says.

The Justice Department is scheduled to announce the findings of its year-long review on Wednesday at Baltimore City Hall. A copy of the report was first posted by the New York Times. The Justice Department later made the report public.

The civil rights inquiry was announced the month after 25-year-old Freddie Gray died of a spinal cord injury suffered in police custody after running from officers who confronted him in a high-crime area. That incident sparked protests and rioting in the city, and it drew attention to what residents said was a long frayed relationship with law enforcement.

Six officers charged in connection with Gray’s death were either acquitted or had their cases dropped.

In the report released Tuesday, Justice Department investigators did not focus, however, on Gray’s death in particular. That is part of a separate, ongoing federal investigation. Instead, they assessed generally how police do their jobs in Baltimore.

Baltimore police officials cooperated with federal authorities, and the report notes that police have already taken steps toward solving the department’s problems, including revising its use-of-force policies and beginning to equip officers with body cameras.

Because of the Justice Department’s investigation, the city probably will have to agree to certain reform proposals, including the possibility of a federal monitor. Baltimore’s police commissioner, Kevin Davis, worked in Prince George’s County, Md., when its department was being monitored by the Justice Department, and he was involved in implementing reforms there.

Spokesmen for the Justice Department declined to comment; the Baltimore Police Department did not immediately respond to messages seeking comment.

Under Attorney General Loretta Lynch, the Justice Department has been aggressive in trying to encourage change in local police departments.

The department sued the city of Ferguson, Mo. — alleging that the police and court system there routinely violated the civil rights of black residents — when officials balked at a tentative agreement. That ultimately persuaded local leaders to agree to policy revisions and more training for members of the city’s police force. Justice also reached a comprehensive settlement with the city of Newark to resolve years-old allegations that city police officers used excessive force, stopped people without just cause and even stole people’s property.

Justice Department reviewers in Baltimore found fault at virtually every level of policing — from training to patrol to investigating complaints — and the report concludes that the department encouraged illegal stops “as a crime suppression technique.”

Baltimore’s former mayor, Martin O’Malley, instituted zero-tolerance policing in 1999, a practice that filled the jails and resulted in more than 100,000 arrests a year. After O’Malley left office in 2007, city leaders cut arrests to about 40,000 and publicly stated that arresting large numbers of people had little impact on curbing crime.

But the Justice Department found that the ingrained strategy continued. Police routinely detained and arrested people without cause, the report says, and even strip-searched them in public. Officers accused of misconduct rarely, if ever, suffered consequences, it says, because of an internal affairs process that was broken.

Police stopped pedestrians and motorists more often in African American neighborhoods, and often without reasonable suspicion. The report says 44 percent of all stops over five years were concentrated in just two small, mostly-black communities, meaning that hundreds of African Americans were stopped at least 10 times, and seven were stopped more than 30 times.

According to the report, one 22-year-old black man was detained merely for walking through an area known for high crime and drugs; another man wearing a hooded sweatshirt on a cold night was stopped because an officer “thought it could be possible that the individual could be out seeking a victim of opportunity.” One black man in his mid-50s was stopped 30 times in less than four years, the report says, and none of the stops resulted in a citation or criminal charge.

The report says many of the department’s raced-based policing practices were encouraged by supervisors who told officers to target African Americans.

The department also was found to have engaged in two kinds of illegal arrests: those without probable cause and those involving people standing legally on public property who were cited for minor offenses such as loitering or trespassing without proper notice. African Americans make up 63 percent of the city’s population but account for 86 percent of criminal charges issued by police.

The report hammers the department’s use-of-force practices. It says officers often employed excessive force on people with mental-health problems, juveniles and people who were restrained and presented no threat to police.

When it came time to review such misuses of force, the department failed to hold officers accountable, the report says. Out of nearly 3,000 force incidents logged over a six-year period, the report says, only 10 were thoroughly investigated and just one was declared excessive.

The report faults supervisors’ monitoring of officers, saying that federal reviewers “did not identify a single stop, search, or arrest” that a front-line supervisor found to violate constitutional standards even though incident reports “describe facially unlawful police action.”

The department discourages the public from filing complaints through a cumbersome process and “frequently” closes out complaints with little effort to reach the person who complained, the report says.

“A cultural resistance to accountability” has developed in the department that leaves serious misconduct unpunished, even in the case of officers who have a reputation for violating department rules and constitutional protections, the report says.